應用多重電極排列法研究土壤及地下水

The application of multiple-array method to investigate contamination of soil and groundwate

王俊傑(Wang -Jiun Jie)

指導教授 ： 游峻一

共同指導教授 ： 詹益臨

健行科技大學/工學院/土木工程系空間資訊與防災科技碩士班/碩士(2015年)

摘要

地電阻影像剖面法探測中，不同的電極排列法的解析度、靈敏度與側向三維效應將影響成像能力，本研究係探討Wenner-Schlumberger、Pole-Pole、Dipole-Diploe、Pole-Diploe與Edge-Gradient等五種電極排列法於台灣土壤及地下水污染場址之適用性並評估各種排列法之優劣。首先先以數值模擬的方式在相同模型與演算法的條件下比較各電極排列的解析能力，並於野外場址實驗中比對電極間距與放電時間等量測參數對於成像能力之影響，最後再將實驗成果真實應用在一個土壤及地下水污染的加油站場址。本研究共計模擬兩種對比性的數值模型，於野外實驗場址中測試四種電極間距。在實驗場址中共量測63筆地電阻影像法資料，在污染場址共佈設6條二維地電阻影像法測線與一組三維地電阻影像法資料。
由數值模擬、野外實驗與污染場址的研究發現，(1) Wenner-Schlumberger具有較佳的資料品質；(2) Wenner-Schlumberger與Edge-Gradient解析能力較高；(3) Dipole-Diploe與Edge-Gradient較易受到側向三維效應的影響，但對於高電阻率的異常物解析能力較好；(4) Pole-Pole法解析能力較低，但受側向三維效應影響最小，且探測深度最深。
依據本研究成果，在土壤及地下水污染調查上建議首先使用Wenner-Schlumberger與Edge-Gradient排列法，在高干擾環境中或為了求得更深之探測深度時，可增加使用Pole-Pole排列法。

關鍵字

地電阻影像法 ； 地下水 ； 污染 ； 電極排列

並列摘要

n Electrical Resistivity Tomography (ERT) survey, different electrode arrays would affect the resolution, sensitivity and the imaging ability may be affected by the lateral 3D effect. This study is to study five electrode configuration applied in groundwater contaminated site in Taiwan, including Wenner-Schlumberger, Pole-Pole, Dipole-Diploe, Pole-Diploe and Edge-Gradient array, to evaluate their advantages and disadvantages. First, use numerical simulation with the same model and algorithm to compare the resolution with the above-mentioned electrode arrays. Second, compare the tomography in the field site with different measurement-parameter such as the interval between two electrodes and the measure time. In the last, apply the investigation results to a soil and groundwater pollution gas station site. In this study, we total simulate two differential models and test four types of electrode intervals in the field site. In the field site, we collected 63 ERT data. And in the pollution site, we conducted 6 survey lines to get 2D electrical resistivity tomography, and one 3D electrical resistivity image data.
From numerical simulation, field site investigation and contaminated site research, we found that (1) Wenner - Schlumberger has better quality of data. (2) Wenner - Schlumberger and Edge-Gradient have higher resolution than others. (3) Dipole-Diploe and Edge-Gradient are easier affected by lateral 3D effect, but their resolutions to high resistivity anomaly are better. (4) Pole-Pole has poor resolution, but its lateral 3D effect is the smallest, and its sounding depth is the deepest.

According to this research results, we suggested that it is better to use Wenner - Schlumberger and Edge-Gradient array to the soil and groundwater contaminated site. If it is in the high noises field site or it needs to do deeper sounding, it could append Pole-Pole array.

並列關鍵字

Electrical Resistivity Tomography(ERT) ； groundwater ； pollution ； electrode configuration array

參考文獻

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